ISLAMABAD, (Reuters) – Gunmen attacked a bus in Pakistan’s southwestern Baluchistan province on Friday, killing at least 18 people including a woman and a child, police said.

Most of the victims died from fire caused by the attack at a petrol station in Khuzdar, a town about a four-hour drive from Quetta. The fire engulfed the van, the petrol station and four nearby shops. No further details were available.

Several militant groups are active in Baluchistan, Pakistan’s biggest but poorest province.

The province faces a revolt by Baluch ethnic separatists, who are fighting a protracted insurgency demanding more autonomy and control over natural resources.

Pro-Taliban militants are active in the province, which borders both Afghanistan and Iran. Sunni Muslim militants also regularly carry out attacks on Baluchistan’s Shi’ite minority.